Cadillac Powertrain Control Module (PCM) Tuning Discussion, Going MAFLess? in Cadillac Engine Technical Discussion; Is there anyone else here with an LT1 that has gone to a MAFLess tune?
I did my own, and ...

Going MAFLess?

Is there anyone else here with an LT1 that has gone to a MAFLess tune?

I did my own, and have not regretted it once since I went. My MAF sits in my toolbox now. My BLM's are so much more stable now than they ever were with the MAF and stock VE Tables.

It is common downunder to ditch the MAF, here in the US tuners seem to like to keep it. Mainly if you do another mod without a MAF, you likley need to go back and retune the VE tables. It isn't a biggie, but I do like the flexability in the air intake now and that I can run my ride without the intake elbow if I want to and no adverse effects whatsoever (save IAT location).

Car is much more stable at high ambient temps, no power dropoff when it is 90+ and I am in heavy traffic. Ever get that soggy feel? Gone. No issues with the MAF being a restriction at anytime. WOT power is best you can get it. Tuners in Australia have worked hard at trying to prove the MAF isn't a problem when tuned properly compared to the same car with a tuned properly MAFLess (aka, Speed Density) tune. The MAFLess tune was always faster in the 1/4 mile.

Me? I just like to play with it! Even got my split BLM's pretty much dialed out, it is very stable now and even.

Re: Going MAFLess?

Is there anyone else here with an LT1 that has gone to a MAFLess tune?

I did my own, and have not regretted it once since I went. My MAF sits in my toolbox now. My BLM's are so much more stable now than they ever were with the MAF and stock VE Tables.

It is common downunder to ditch the MAF, here in the US tuners seem to like to keep it. Mainly if you do another mod without a MAF, you likley need to go back and retune the VE tables. It isn't a biggie, but I do like the flexability in the air intake now and that I can run my ride without the intake elbow if I want to and no adverse effects whatsoever (save IAT location).

Car is much more stable at high ambient temps, no power dropoff when it is 90+ and I am in heavy traffic. Ever get that soggy feel? Gone. No issues with the MAF being a restriction at anytime. WOT power is best you can get it. Tuners in Australia have worked hard at trying to prove the MAF isn't a problem when tuned properly compared to the same car with a tuned properly MAFLess (aka, Speed Density) tune. The MAFLess tune was always faster in the 1/4 mile.

Me? I just like to play with it! Even got my split BLM's pretty much dialed out, it is very stable now and even.

I would like to try it. If you say it works better and you don;t have adverse effects, I would love to try it. I should have my software this week. (Tunercat). I should also have my cable this week too. I will let you know.

Re: Going MAFLess?

I'm still planning on getting some more info from you on this and other general tuning matters, as soon as I ever pick up a cable and/or other software (from playing around a bit, I guess the free TunerProRT is still worthwhile enough).

My '95 "base" FWB is just begging for a better shift pattern and feel, and whatever other little helpers it can get to improve general performance computer-wise.

Essentially, whatever the best tune you've done for your own car, but made to work with a 2:93 rear.

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Re: Going MAFLess?

Originally Posted by caddycruiser

Essentially, whatever the best tune you've done for your own car, but made to work with a 2:93 rear.

I would suggest lowering the fan turn-on temp for your primary fan in addition to whatever NODIH modifies his program (like 2.93 gears) to accomodate your car since he has the primary mechanical fan on his.
Lowering fan temps is one of the most beneficial reasons to alter the stock PCM tune.

Re: Going MAFLess?

Originally Posted by N0DIH

First make sure you have a dialed in tune. If you are stock, I can help a lot with that. I haven't messed with radial cammed engines or loose converters yet.....

I am essentially stock, with the exception of freer flowing exhaust. I am looking to get a RAISS intake and 1.6 rockers and better valve springs in the near future, but have none of that now. I have the 2.93 gears and am looking to get better shift patterns and bassically what you have done to yours. The big upgrades are a long time a comin'.

Re: Going MAFLess?

Originally Posted by BCs71

I would suggest lowering the fan turn-on temp for your primary fan in addition to whatever NODIH modifies his program (like 2.93 gears) to accomodate your car since he has the primary mechanical fan on his.
Lowering fan temps is one of the most beneficial reasons to alter the stock PCM tune.

Good point. Everything he has described about his tune seems dead on, it's just trying to get that same thing adapted to work with the 2:93 and the electric fans.

Re: Going MAFLess?

Yup, I can do 2.93's with a similar program that I have, only I have 3.42's. Mine is somewhat based on the V4P package, as it is intended to be in more of a power mode most of the time, due to the expectation of up to a 7000# trailer. But it sure makes a great running, very responsive car.

We have to consider that we might be able to redline at 5800-5900 fairly safe (so I am told), but I don't shift there, I found my car is actually slower when I try to shift near redline. I find that I am faster at 5400 rpm shift points. But if you have more cam like BCs71, likely you can gain some by shifting higher rpms.

My tune is pretty solid for trans. I like it a lot, and anytime you blip the throttle, you are 90% of the time in the gear that you would want to be in. It is nice to be able to nail the gas and you have instant great acceleration, no lag time for shifts, no delays, no waiting for the engine to rev and downshift for acceleration.

Originally Posted by caddycruiser

Good point. Everything he has described about his tune seems dead on, it's just trying to get that same thing adapted to work with the 2:93 and the electric fans.

Which I have never needed any fan temp changes, the mech fan keeps the primary coolant temps very stable, in the 85-92C range, in most any weather. With the dual electrics, the temps are allowed to run to where they go until it hits the 220F or so upper temp limit for fan 1. Easy tweaks.

Re: Going MAFLess?

That sounds terrific, just like in our emails, and as soon as I get a cable, I will get back in touch with you...aside of everything, I think just the basic tuning of the car is what I dislike most. Give me V4P-like improved, mafless, etc., and all to mesh properly with the 2:93s and fans, and that would be terrific.

Not to get too off topic regards to tuning, but with your MAF now removed (I want to do the same with mine), how does your air intake setup work as far as that small gap? I only wonder, because stock I guess just any short tubing piece would be fine, but a lot of aftermarket setups seem to depend on the MAF as a bit of a mounting fixture.

And, though I forgot now, would I be able to do this with the TunerProRT or would Tunercat be a necessity...basically just flashing from one program to a new?

Re: Going MAFLess?

I have a 1 foot or so piece of PVC painted black and a Vortec 350/454 K&N Filter on it ($49 or so at Walmart). It has maybe a little more surface area than the stock filter, which can't hurt. I think most K&N or the like cone filters are actually smaller than stock. No gaps at all.

TunerPro should work, but I have never flashed with it, if it even can. WinFlash can flash for you and is free for 30 days at tunercat.com, and is only $20 if you buy it. Then use TunerProRT to tune, and WinFlash to flash.

Re: Going MAFLess?

Originally Posted by N0DIH

I have a 1 foot or so piece of PVC painted black and a Vortec 350/454 K&N Filter on it ($49 or so at Walmart). It has maybe a little more surface area than the stock filter, which can't hurt. I think most K&N or the like cone filters are actually smaller than stock. No gaps at all.

TunerPro should work, but I have never flashed with it, if it even can. WinFlash can flash for you and is free for 30 days at tunercat.com, and is only $20 if you buy it. Then use TunerProRT to tune, and WinFlash to flash.

Sounds great--I emailed you with essentially the same stuff I talked about here.

The other question is, I think mentioned before, but would you also still need me to first give you the stock file from my '95, or did you already have one?

Re: Going MAFLess?

Something else I just thought of, particularly with the MAFLESS deal.

For quite some time, I've been thinking of different air intake setups and weighing the pros and cons of each, and am still most interested in an "all in front" setup that basically eliminates all tubes and baffles and is a direct air shot right into the TB. Not saying for sure that's what I'd do, as a lot of people have had the same results with a basic cheap pipe, etc. to the side, but it does bring up an interesting question.

When you do one of these setups, the MAF gets moved to right in front of the TB and then the filter in front of that. For the majority, most just install these things as is on their MAF'd cars, and never have an issue--just much better breathing--and no tuning whatsoever. A few, though, have run into issues because of the excess new air being let in, with backfiring, etc. and had to have air/fuel mixtures touched up just a tad to fix it.

SO, long story short, if in theory you were to do the same kind of setup--essentially filter off TB--WITHOUT a MAF, would there be any new issues and/or would that require additional custom tuning work to get right?

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Re: Going MAFLess?

Originally Posted by caddycruiser

SO, long story short, if in theory you were to do the same kind of setup--essentially filter off TB--WITHOUT a MAF, would there be any new issues and/or would that require additional custom tuning work to get right?

IMO, if I were to consider going speed density (MAFless), I would be sure to have all my mods completed and then take extensive logging data to know exactly what my car is doing. The data would then let me know if all other engine components and sensors are running properly. After all necessary sensors are running properly, I would then get the program tweaked to remove the MAF.

I like having my MAF though as peace of mind that any changes in mods or sensor degredation should be compensated for by the MAF since everything was designed to work that way from the factory and its engineers, a bunch of guys way smarter than I am.
Admittedly, though, I am not the most educated on tuning and what all benefits and drawbacks there are to going speed density.

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Re: Going MAFLess?

Originally Posted by N0DIH

We have to consider that we might be able to redline at 5800-5900 fairly safe (so I am told), but I don't shift there, I found my car is actually slower when I try to shift near redline. I find that I am faster at 5400 rpm shift points. But if you have more cam like BCs71, likely you can gain some by shifting higher rpms.

More cam does help, but also the stock valve springs float for just about everyone I know of anywhere above 5300rpms (depends on age, rocker tolerances, etc.). So aftermarket springs would easily allow 5800rpms with the stock cam. Of course, this would only be used anyway at WOT.

Re: Going MAFLess?

Good points. I still do worry about going without the MAF, but only feel more confident because N0DIH has apparently had such great success without his in a higher mileage car.

Something tells me still to keep it, but I at least want to try a tune from him without first. At the same time, wondering what other issues can come up without it being there...just like you mentioned.